Scientific Name
Strombocactus disciformis (DC.) Britton & Rose
Synonym(s)
Strombocactus disciformis subsp. disciformis, Mammillaria disciformis, Ariocarpus disciformis, Pediocactus disciformis
Scientific Classification
Family: Cactaceae
Subfamily: Cactoideae
Tribe: Cacteae
Genus: Strombocactus
Description
Strombocactus disciformis is a rare cactus with a turnip-like root and a small, nearly spherical stem covered with overlapping, spirally arranged tubercles, each with a spine-bearing areole at its tip. The stem is blue-green with a grayish tinge, has a slightly depressed apex, and can grow up to 3.2 inches (8 cm) tall and 3.6 inches (9 cm) in diameter. The spines are erect, dark grey at the tips, pale grey at the base, and up to 0.8 inches (2 cm) long. Each areole bears 4 to 5 spines.
The flowers are shiny, cream-colored, measure up to 1.4 inches (3.5 cm) in diameter, and appear from the new growth at the tip of the stem in early spring.
Hardiness
USDA hardiness zones 10b to 11b: from 35 °F (+1.7 °C) to 50 °F (+10 °C).
How to Grow and Care
To encourage better flowering, allow the plants to enjoy a cooling period in the winter and suspend watering. Unlike many other cacti, which use their ribs as storage devices, Mammillaria feature raised tubercles, from which spines emerge. When you water, the tubercles will expand to increase water storage. The flowers emerge from the axils of these tubercles on the previous year's growth, which accounts for their interesting halo effect. The cactus mustn't be exposed to prolonged dampness and sitting water. Never let your cactus sit in a dish of water. Lastly, ensure to fertilize during the growing season for the best results.
Repot as needed, preferably during the warm season. To repot Mammillaria, ensure the soil is dry before repotting, then gently remove the pot. Knock away the old soil from the roots, removing any rotted or dead roots. Treat any cuts with a fungicide. Place the plant in its new pot and backfill it with potting soil, spreading the roots as you repot. Leave the plant dry for a week or so, then begin to water lightly to reduce the risk of root rot.
See more at How to Grow and Care for Mammillaria.
Origin
Strombocactus disciformis is native to central and northeast Mexico.
Links
- Back to genus Strombocactus
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus
Photo Gallery
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